The liberal Supreme Court justice said Monday that an even-number bench doesn't trouble him, undercutting one of the arguments made by Democrats to fill the current vacancy quickly.

Breyer, speaking at the Annual Burton Awards Ceremony at the Library of Congress, said he researched the number of times in the past when the court didn't need a ninth vote to reach a decision, and said it would've only made an impact in a few cases of the 70 to 80 that they hear each year.

"See we're unanimous 50% of the time. And 20% of the time, we're 5-4," Breyer said, explaining that he did not feel the Supreme Court was diminished without an immediate fill-in for Justice Antonin Scalia, who died earlier this year. "And so I said, 'How many cases are there that Nino's vote would have made a difference? I think there were four or five."

And Breyer put a finer point on it: If there's a 4-4 stalemate, it will just means the Supreme Court won't overstep its bounds. The decision of the lower court is upheld when the Supreme Court stalemates.

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"if you believe that the Supreme Court should decide all the major issues for the country, I guess you'd like them all decided," Breyer said. "I happen not to believe that."

President Barack Obama named Judge Merrick Garland in March to fill the ninth spot on the bench, but Senate Republicans do not plan any hearings or vote on the nomination, and pressure by Democrats to move the GOP on the issue has failed to do so.